Polymer coated urea in 'Russet Burbank' potato: yield and tuber quality

Authors: TAYSOM, TRENT - Miller Research, Inc; LEMONTE, JOSHUA - Brigham Young University; Ransom, Curtis; STARK, JEFFREY - University Of Idaho; HOPKINS, AUSTIN - Colorado State University; HOPKINS, BRYAN - Brigham Young University

Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2023
Publication Date: 12/1/2023
Citation: Taysom, T.W., LeMonte, J.J., Ransom, C.J., Stark, J.C., Hopkins, A.P., Hopkins, B.G. 2023. Polymer coated urea in 'Russet Burbank' potato: yield and tuber quality. American Journal of Potato Research. 100:451-463. https://doi.org/10.1007/s12230-023-09931-5.
DOI: https://doi.org/10.1007/s12230-023-09931-5

Interpretive Summary: Enhanced fertilizer technologies (e.g., polymer coated urea) allow for nitrogen fertilizer to slowly be released into the soil—which can help improve yields and reduce nitrogen related environmental issues. Understanding how the use of this fertilizer technology changes other nitrogen management practices (e.g., fertilizer rate, application timing, and placement) needs to be understood to maximize potato yield and quality. This investigation looked at the effect of using polymer coated urea in a single application compared to the standard grower’s practice (i.e., urea split applied with half the urea applied before plant emergence and the remaining amount applied in three equal portions throughout the growing season). Russet Burbank potatoes were grown on three fields in Idaho in 2006 to 2007. Fertilizer was applied at five different rates (0, 33, 67, 100, and 133% of the recommended rate of each field) for urea split-applied, urea applied all at emergence, or polymer coated urea applied all at emergence. The polymer coated urea treatment effectively met all the potato’s seasonal nitrogen requirements. This treatment resulted in high quality (i.e., no visible defects), more marketable quantity (i.e., good shape and size), and increased tuber weights (by 11%, 11%, and 10%, respectively) than the grower standard practice of split applying urea. Using polymer coated urea could be more economical (reduced cost of additional applications) and environmentally safe (reduced nitrogen lost to the environment).

Technical Abstract: Polymer coated urea (PCU) is a temperature-based controlled release fertilizer source that efficiently matches N demand. PCU may have the potential to increase potato (Solanum tuberosum L.) tuber yield and quality, while providing environmental benefits with a more convenient and less labor-intensive N fertilization system. The objectives of this study were to determine the effects of single-application PCU on potato yield and quality. Russet Burbank potato was grown at three locations with semi-arid, alkaline, volcanic sand-based loam soil conditions in Idaho, USA in 2006 and 2007. Five rates of N (0, 33, 67, 100, and 133% of the recommended rate) were applied as either split-applied urea (similar to grower standard practices), urea, or PCU applied all at emergence. The PCU-fertilized treatments produced higher US No. 1, marketable, and total tuber yields (by 11%, 11%, and 10%, respectively) than the grower standard practice of split urea fertilizations. The PCU-fertilized treatments also trended toward increased tuber size, yielding 30% more in the largest US No. 1 category. These results suggest that a single application of PCU fertilizer can efficiently meet seasonal N requirements for Russet Burbank potatoes.